GaAs-on-InP heteroepitaxial waveguides grown by molecular beam epitaxy

Abstract

The GaAs-on-InP heteroepitaxial waveguides are demonstrated for the first time using molecular beam epitaxy. A propagation loss of 9.3 dB/cm was obtained for waveguides grown on a 3° off (100) InP substrate. Compared to the 16 dB/cm loss for waveguides on (100) InP substrates, the waveguides on misoriented InP substrates exhibited a significantly lower loss. Based on photoluminescence studies, we attribute the propagation loss in both samples mainly to optical absorption by crystal defects. Defect densities of 4×1017 cm−3 and 2×1017 cm−3 are estimated for material on (100) and 3° off (100) substrates, respectively. Such heteroepitaxial waveguides may have applications in long-wavelength photonic integrated circuits.